Cita APA (7a ed.)

Welsh, J., & Elder, J. (1987). Introduction to Modula-2. Prentice-Hall.

Cita Chicago Style (17a ed.)

Welsh, Jim, y John Elder. Introduction to Modula-2. New York [etc.]: Prentice-Hall, 1987.

Cita MLA (9a ed.)

Welsh, Jim, y John Elder. Introduction to Modula-2. Prentice-Hall, 1987.